1. Field of Invention
The invention relates to color toner and developer compositions, and more specifically, to color toner and developer compositions that include very large or ultra large external additives, in particular latex particles, among other conventionally sized external additives, on external surfaces of the toner particles.
2. Description of Related Art
U.S. Pat. No. 5,763,132, incorporated herein by reference in its entirety, describes a process for decreasing toner adhesion and decreasing toner cohesion, which comprises adding a hard spacer component of a polymer of polymethyl methacrylate (PMMA), a metal, a metal oxide, a metal carbide, or a metal nitride, to the surface of a toner comprised of resin, wax, compatibilizer, and colorant excluding black, and wherein toner surface additives are blended with said toner, and wherein said component is permanently attached to the toner surface by the injection of said component in a fluid bed milling device during the size reduction process of said toner contained in said device, and where the power imparted to the toner to obtain said attachment is from equal to, or about above 5 watts per gram of toner. See the Abstract and column 1, lines 9-28.
U.S. Pat. No. 5,716,752, incorporated herein by reference in its entirety, describes a process for decreasing toner adhesion and decreasing toner cohesion, which comprises adding a component of magnetite, a metal, a metal oxide, a metal carbide, or a metal nitride to the surface of a toner comprised of resin, wax, and colorant, and wherein toner surface additives are blended with said toner, and wherein said component is permanently attached to the toner surface by the injection of said component in a fluid bed milling device during the size reduction process of said toner contained in said device, and where the power imparted to the toner to obtain said attachment is from equal to, or about above 5 watts per gram of toner. See the Abstract.
Neither of these references teaches the possible use of latex particles as spacers. In fact, both references require that the spacers described therein be attached to the toner particles with high power injection in a fluid bed milling device during the size reduction (grinding) step, thereby requiring the use of hard spacer particles. Softer latex particles thus could not be used in such attachment method as they would be crushed or buried into the toner particles, and thus rendered ineffective for their intended purpose. Further, neither reference teaches a method of attaching the spacers to the toner particles after completion of grinding by, for example, blending.
Alternative ultra large external additives that act as spacers on toners are still desired, as are spacers that might be applied in methods less intensive than the application methods described in each of U.S. Pat. Nos. 5,763,132 and 5,716,752.